This patch adds a ASoC driver for the AXI-SPDIF core. The core implements a simple SPDIF transmitter and is used on some Analog Devices' reference designs for various FPGA platforms. For now the driver only support the PL330 as the the DMA controller.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de --- Has a compile time dependency on topic/dma --- sound/soc/adi/Kconfig | 8 ++ sound/soc/adi/Makefile | 2 + sound/soc/adi/axi-spdif.c | 272 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 282 insertions(+) create mode 100644 sound/soc/adi/axi-spdif.c
diff --git a/sound/soc/adi/Kconfig b/sound/soc/adi/Kconfig index 14bb385..82438de 100644 --- a/sound/soc/adi/Kconfig +++ b/sound/soc/adi/Kconfig @@ -11,3 +11,11 @@ config SND_SOC_ADI_AXI_I2S select REGMAP_MMIO help ASoC driver for the Analog Devices AXI-I2S softcore peripheral. + +config SND_SOC_ADI_AXI_SPDIF + tristate "AXI-SPDIF support" + depends on SND_SOC_ADI + select SND_SOC_GENERIC_DMAENGINE_PCM + select REGMAP_MMIO + help + ASoC driver for the Analog Devices AXI-SPDIF softcore peripheral. diff --git a/sound/soc/adi/Makefile b/sound/soc/adi/Makefile index d32c21a..64456c1 100644 --- a/sound/soc/adi/Makefile +++ b/sound/soc/adi/Makefile @@ -1,3 +1,5 @@ snd-soc-adi-axi-i2s-objs := axi-i2s.o +snd-soc-adi-axi-spdif-objs := axi-spdif.o
obj-$(CONFIG_SND_SOC_ADI_AXI_I2S) += snd-soc-adi-axi-i2s.o +obj-$(CONFIG_SND_SOC_ADI_AXI_SPDIF) += snd-soc-adi-axi-spdif.o diff --git a/sound/soc/adi/axi-spdif.c b/sound/soc/adi/axi-spdif.c new file mode 100644 index 0000000..806fc8f --- /dev/null +++ b/sound/soc/adi/axi-spdif.c @@ -0,0 +1,272 @@ +/* + * Copyright (C) 2012-2013, Analog Devices Inc. + * Author: Lars-Peter Clausen lars@metafoo.de + * + * Licensed under the GPL-2. + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/clk.h> +#include <linux/regmap.h> + +#include <sound/core.h> +#include <sound/pcm.h> +#include <sound/pcm_params.h> +#include <sound/soc.h> +#include <sound/initval.h> +#include <sound/dmaengine_pcm.h> + +#define AXI_SPDIF_REG_CTRL 0x0 +#define AXI_SPDIF_REG_STAT 0x4 +#define AXI_SPDIF_REG_TX_FIFO 0xc + +#define AXI_SPDIF_CTRL_TXDATA BIT(1) +#define AXI_SPDIF_CTRL_TXEN BIT(0) +#define AXI_SPDIF_CTRL_CLKDIV_OFFSET 8 +#define AXI_SPDIF_CTRL_CLKDIV_MASK (0xff << 8) + +#define AXI_SPDIF_FREQ_44100 (0x0 << 6) +#define AXI_SPDIF_FREQ_48000 (0x1 << 6) +#define AXI_SPDIF_FREQ_32000 (0x2 << 6) +#define AXI_SPDIF_FREQ_NA (0x3 << 6) + +struct axi_spdif { + struct regmap *regmap; + struct clk *clk; + struct clk *clk_ref; + + struct snd_dmaengine_dai_dma_data dma_data; + + struct snd_ratnum ratnum; + struct snd_pcm_hw_constraint_ratnums rate_constraints; +}; + +static int axi_spdif_trigger(struct snd_pcm_substream *substream, int cmd, + struct snd_soc_dai *dai) +{ + struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); + unsigned int val; + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_RESUME: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + val = AXI_SPDIF_CTRL_TXDATA; + break; + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + val = 0; + break; + default: + return -EINVAL; + } + + regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL, + AXI_SPDIF_CTRL_TXDATA, val); + + return 0; +} + +static int axi_spdif_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *params, struct snd_soc_dai *dai) +{ + struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); + unsigned int rate = params_rate(params); + unsigned int clkdiv, stat; + + switch (params_rate(params)) { + case 32000: + stat = AXI_SPDIF_FREQ_32000; + break; + case 44100: + stat = AXI_SPDIF_FREQ_44100; + break; + case 48000: + stat = AXI_SPDIF_FREQ_48000; + break; + default: + stat = AXI_SPDIF_FREQ_NA; + break; + } + + clkdiv = DIV_ROUND_CLOSEST(clk_get_rate(spdif->clk_ref), + rate * 64 * 2) - 1; + clkdiv <<= AXI_SPDIF_CTRL_CLKDIV_OFFSET; + + regmap_write(spdif->regmap, AXI_SPDIF_REG_STAT, stat); + regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL, + AXI_SPDIF_CTRL_CLKDIV_MASK, clkdiv); + + return 0; +} + +static int axi_spdif_dai_probe(struct snd_soc_dai *dai) +{ + struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); + + snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL); + + return 0; +} + +static int axi_spdif_startup(struct snd_pcm_substream *substream, + struct snd_soc_dai *dai) +{ + struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); + int ret; + + ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0, + SNDRV_PCM_HW_PARAM_RATE, + &spdif->rate_constraints); + if (ret) + return ret; + + ret = clk_prepare_enable(spdif->clk_ref); + if (ret) + return ret; + + regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL, + AXI_SPDIF_CTRL_TXEN, AXI_SPDIF_CTRL_TXEN); + + return 0; +} + +static void axi_spdif_shutdown(struct snd_pcm_substream *substream, + struct snd_soc_dai *dai) +{ + struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); + + regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL, + AXI_SPDIF_CTRL_TXEN, 0); + + clk_disable_unprepare(spdif->clk_ref); +} + +static const struct snd_soc_dai_ops axi_spdif_dai_ops = { + .startup = axi_spdif_startup, + .shutdown = axi_spdif_shutdown, + .trigger = axi_spdif_trigger, + .hw_params = axi_spdif_hw_params, +}; + +static struct snd_soc_dai_driver axi_spdif_dai = { + .probe = axi_spdif_dai_probe, + .playback = { + .channels_min = 2, + .channels_max = 2, + .rates = SNDRV_PCM_RATE_KNOT, + .formats = SNDRV_PCM_FMTBIT_S16_LE, + }, + .ops = &axi_spdif_dai_ops, +}; + +static const struct snd_soc_component_driver axi_spdif_component = { + .name = "axi-spdif", +}; + +static const struct regmap_config axi_spdif_regmap_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + .max_register = AXI_SPDIF_REG_STAT, +}; + +static int axi_spdif_probe(struct platform_device *pdev) +{ + struct axi_spdif *spdif; + struct resource *res; + void __iomem *base; + int ret; + + spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL); + if (!spdif) + return -ENOMEM; + + platform_set_drvdata(pdev, spdif); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_request_and_ioremap(&pdev->dev, res); + if (!base) + return -EBUSY; + + spdif->regmap = devm_regmap_init_mmio(&pdev->dev, base, + &axi_spdif_regmap_config); + if (IS_ERR(spdif->regmap)) + return PTR_ERR(spdif->regmap); + + spdif->clk = devm_clk_get(&pdev->dev, "axi"); + if (IS_ERR(spdif->clk)) + return PTR_ERR(spdif->clk); + + spdif->clk_ref = devm_clk_get(&pdev->dev, "ref"); + if (IS_ERR(spdif->clk_ref)) + return PTR_ERR(spdif->clk_ref); + + ret = clk_prepare_enable(spdif->clk); + if (ret) + return ret; + + spdif->dma_data.addr = res->start + AXI_SPDIF_REG_TX_FIFO; + spdif->dma_data.addr_width = 4; + spdif->dma_data.maxburst = 1; + + spdif->ratnum.num = clk_get_rate(spdif->clk_ref) / 128; + spdif->ratnum.den_step = 1; + spdif->ratnum.den_min = 1; + spdif->ratnum.den_max = 64; + + spdif->rate_constraints.rats = &spdif->ratnum; + spdif->rate_constraints.nrats = 1; + + ret = devm_snd_soc_register_component(&pdev->dev, &axi_spdif_component, + &axi_spdif_dai, 1); + if (ret) + goto err_clk_disable; + + ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, + SND_DMAENGINE_PCM_FLAG_NO_RESIDUE); + if (ret) + goto err_clk_disable; + + return 0; + +err_clk_disable: + clk_disable_unprepare(spdif->clk); + return ret; +} + +static int axi_spdif_dev_remove(struct platform_device *pdev) +{ + struct axi_spdif *spdif = platform_get_drvdata(pdev); + + clk_disable_unprepare(spdif->clk); + + return 0; +} + +static const struct of_device_id axi_spdif_of_match[] = { + { .compatible = "adi,axi-spdif-tx-1.00.a", }, + {}, +}; +MODULE_DEVICE_TABLE(of, axi_spdif_of_match); + +static struct platform_driver axi_spdif_driver = { + .driver = { + .name = "axi-spdif", + .owner = THIS_MODULE, + .of_match_table = axi_spdif_of_match, + }, + .probe = axi_spdif_probe, + .remove = axi_spdif_dev_remove, +}; +module_platform_driver(axi_spdif_driver); + +MODULE_AUTHOR("Lars-Peter Clausen lars@metafoo.de"); +MODULE_DESCRIPTION("AXI SPDIF driver"); +MODULE_LICENSE("GPL");